This invention relates to sight glass devices, and in particular, to a sight glass for indicating the state of a fluid in a fluid system having a simplified construction. While the device is described with particular reference to refrigeration systems, those skilled in the art will recognize the wider applicability of the invention disclosed hereinafter.
Sight glasses of various types and constructions are well known in the art. One area where sight glasses find application is in refrigeration systems where the device is inserted in the refrigerant line. The sight glass enables maintenance or operational personnel to observe certain states of the fluid passing through the line. In general, prior art sight devices only permit indication of a full or empty condition of the fluid line. A partially full condition in the fluid line, generally a prelude to the empty condition, is not easily detected.
This invention disclosed hereinafter differs from known prior art sight glass devices in that the visual presentation made to an observer has a distinct presentation for all conditions possible in the system with which the sight glass finds utility. That is, the sight glass of this invention is capable of illustrating a partially full condition in the liquid line as one visual presentation, yet shows a second, distinct visual indication for a completely full liquid line. In addition, the structure highly magnifies any bubbles of gas passing through the fluid system.
One of the objects of this invention is to provide a low-cost sight glass device.
Another object of this invention is to provide a sight glass capable of showing the flow condition in a fluid line.
Another object of this invention is to provide a sight glass which differentiates between a full liquid flow condition and a partial liquid flow condition in a fluid line.
Still another object of this invention is to provide a sight glass for use in a fluid line which magnifies minute bubbles of gas in the fluid passing the sight glass.
Other objects of this invention will be apparent to those skilled in the art in light of the following description and accompanying drawings.